Sentence Case Converter: Perfect First Letter Capitalization
Transform any text into properly formatted sentences with our intelligent sentence case converter. Whether you're fixing formatted text, preparing documents, or cleaning up content, our tool automatically capitalizes the first letter of each sentence while converting the rest to lowercase. Perfect for professional writing, academic papers, and social media posts.
Capitalizes only the first letter of each sentence, producing clean, grammatically correct output from all-caps, all-lowercase, or mixed-case input in a single step.
Handles multiple paragraphs and line breaks correctly — each sentence after a period, exclamation mark, or question mark is individually capitalized without affecting the rest.
Preserves acronyms, proper nouns, and intentional capitalization within sentences rather than blindly lowercasing everything after the first word.
Processes any length of text without limits — paste an entire blog post, email draft, or article and get properly cased output ready to review.
Fixes Caps Lock accidents, all-uppercase pastes from PDFs, and inconsistently-cased imported content in one operation rather than word by word.
Free to use in any browser with no registration or extension required.
How to Use
Copy and paste your text into the left input box
Watch it transform to sentence case instantly
Review the converted text in the right box
Click 'Copy' or Download' to use your converted text
Professional Writing
- Business emails
- Report formatting
- Document preparation
- Academic papers
Content Creation
- Blog posts
- Article formatting
- Social media content
- Marketing materials
Text Clean-up
- Fixing CAPS LOCK text
- Correcting mixed case
- Standardizing documents
- Newsletter formatting
| Original Text | Result |
|---|---|
THIS IS A SAMPLE TEXT. ANOTHER SENTENCE. | This is a sample text. Another sentence. |
what about questions? does it work? | What about questions? Does it work? |
hello. my name is john. i live in new york. | Hello. My name is john. I live in new york. |
THE QUICK BROWN FOX. JUMPS OVER. | The quick brown fox. Jumps over. |
Document Platforms
- Microsoft Word
- Google Docs
- Apple Pages
- LibreOffice
Online Platforms
- Gmail
- WordPress
- Medium
- Social Media
When copying text from a PDF, scanned document, or legacy system that outputs everything in uppercase, sentence case is usually the right first pass — it restores readable grammar without over-capitalizing the way title case would.
For LinkedIn posts and professional bio text, sentence case reads as natural and polished — it matches how the platform's own UI is written and avoids the slightly formal register that title case creates in long-form content.
After converting, do a quick scan for brand names with unconventional capitalization — iPhone, eBay, WordPress, YouTube — and restore them manually. The tool cannot know which lowercase words are brand names versus common nouns.
Sentence case is the correct style for most body text in journalism and publishing style guides (AP, Chicago, Guardian), so use it as your default for article drafts before applying tool-specific heading styles.
Use sentence case on imported user-generated content — comments, reviews, support tickets — before displaying them in a UI, so they present consistently regardless of how the user originally typed them.
Use sentence case as your default for body paragraphs, email body text, and social media post copy — it is the most readable and grammatically natural case style for running text, and deviating from it requires a deliberate reason.
Maintain consistency within a document: if headings are in sentence case, keep all headings in sentence case rather than mixing with title case partway through — inconsistency is more noticeable than the choice of convention itself.
Always do a post-conversion review for proper nouns, brand names with internal capitalization (JavaScript, iOS, GitHub), and initialisms (API, HTML, UK) — automatic converters cannot distinguish between a common noun and a proper noun without a dictionary lookup.
For email subject lines, sentence case is increasingly preferred over title case in B2C marketing — A/B tests by major email platforms consistently show higher open rates for sentence-case subject lines, which read as more personal and less promotional.
When processing multilingual content, be aware that sentence case rules differ by language — German capitalizes all nouns, not just sentence starters, so a German sentence converted with an English sentence-case tool will lose required capitalization.
Frequently Asked Questions
Find answers to common questions about our tools and services.
Understanding Sentence Case
Sentence case is the default capitalization style for standard written English: the first letter of each sentence is uppercase, proper nouns retain their capitals, and everything else is lowercase. It is the style used in most newspapers, books, websites, and professional correspondence — the baseline that other case styles deviate from for specific effects. Despite being the most natural-reading option for body text, it is frequently violated in digital content through Caps Lock accidents, bad PDF exports, and copy-pasted content from systems that output in ALLCAPS or inconsistent mixed case.
The most common workflow where this tool is useful is cleaning up imported or copy-pasted text. Content migrated from older CMS platforms, exported from PDFs, or copied from legacy enterprise systems frequently arrives in unexpected case — sometimes all uppercase from a database field that stored text in caps, sometimes in alternating or random case from a formatting bug. Pasting that text into this converter and converting to sentence case gives you a clean, readable baseline that you can then review for proper nouns rather than fixing capitalization word by word.
For content creators managing LinkedIn posts, Medium articles, or blog drafts, sentence case is both the grammatically correct choice for body text and increasingly the preferred choice for headings. Publications like The Guardian, The Atlantic, and most tech blogs use sentence case headings — it avoids the slightly stiff formality of Title Case Every Word and keeps the page hierarchy feeling natural rather than bureaucratic.
Without this tool, the alternatives are: retyping (prohibitively slow for long text), using Microsoft Word's Change Case feature (requires Word to be open, does not handle all edge cases correctly), or writing a regex substitution (s/(?<=.)s+w/..., which breaks on abbreviations and dialogue). This converter handles the common cases reliably and is available instantly in any browser.
Sentence case is the correct style for: body paragraphs in journalism, blog posts, and documentation; email body text and subject lines in most modern brand guidelines; UI labels and button text in Google's Material Design and Apple's Human Interface Guidelines; caption text under images in most editorial and social media contexts; and most academic body text outside of headings. It is not the right choice for page titles in applications (where title case is convention), legal document headings, or short-form labels where all-caps or capitalized case creates better scanability.